Monthly Averages

The
section "Time Series and Monthly Means" in the PACS-SONET homepage had
not been updated in the last two years or so. With the January 2004 monthly summary we have resumed a task
that is essential for the project and serves several purposes, among them:

a) To show all the participants the importance of sending good data
and improving the efficiency of the network,

b) To identify bias in the wind measurements by means of the analysis
of the mean flow,

c) To identify errors in the daily data and to contribute to the control
of quality of the historical database.
d) To maintain the interest of the participants and to increase the frequency
of their visits to the page, presenting/displaying new material that, we
hope, is relevant for both rutine forecast and applied research activities.

We are specially interested
in having the observers review the statistics we will be presenting every
month on the operation of the network so they feel motivated to do a better
job during upcoming months. We are certain that the observers perform better
when they perceive that the data are being used and that their work has
a purpose. Also, we hope that the coordinators and other participants in
the different countries see in this exercise a support to their daily activities.

For the identification
of possible bias in the observations, we have generated maps with monthly
averages of the wind data, using observations from the pilot balloon stations
and from the regular radiosonde network. Although we are not displaying
an analysis along with the maps, we hope that many participants will feel
motivated to make their own analysis and to determine if the special PACS-SONET
observations are good in quality and if these have a significant impact
in the density of the regular upper-air network.

The time series graphs
allow for quick assessment of daily changes in the atmospheric circulation.
Furthermore, we can notice some errors that unfortunately still exist in
the data, but we hope that displaying them will serve as a motivation to
the observers so they will take greater care when reading the angles
and processing the soundings. A few days or weeks after publishing the graphs,
we will generate the maps again using a corrected version of the data.

We look forward to hear your
comments about these products and your suggestions on any changes
or new material that you would like to see included in upcoming summaries.